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61.
M. Vos G.A. Sawatzky M. Davies P. Weightman P.T. Andrews 《Solid State Communications》1984,52(2):159-162
We show that the local impurity density of states and the impurity electron—electron interactions can be obtained from impurity Auger spectra. For a Ag0.95Pd0.05 alloy we find 11% Pd(d) character in the Ag d band and Pd(4d-4d) Coulomb interactions which are much larger than the virtual bound state widths. 相似文献
62.
Hubert G. Theuns Guus F. La Vos Michael C. ten Noever de Brauw Cornelis A. Salemink 《Tetrahedron letters》1984,25(37):4161-4162
Photochemical irradiation of the morphinan alkaloid thebaine 1 followed by reduction, affords the dibenz[d,f]azonine alkaloids neodihydrothebaine 2 and bractazonine 3, in a sequence paralleling the proposed biosynthesis of these alkaloids in Papaver bracteatum. 相似文献
63.
Reaction of 2,6-dimethylphenyl(diphenylmethylene)phosphine (1) with selenium in benzene leads to the compound P-2,6-dimethylphenyl-C,C-diphenylselenophosphene (2c). Compound 2c is stable at room temperature, but decomposes on heating with partial regeneration of the starting materials. Ethanol adds to the PC bond of 2c to give the selenophosphinate 3c. No reaction was observed between 1 and tellurium. 相似文献
64.
3-cyano-2,2-dimethyl cyclopropane-1-carboxylic acid obtained in 62% yield from isobutyraldehyde1, dimethylmalonate, NBS and NaCN is readily transformed to tittle compounds precursors of potent natural and unatural pyrethrinoic insecticides2. 相似文献
65.
Absorbance-detected magnetic resonance (ADMR) of the light-harvesting complex LHC II of spinach revealed two triplet contributions, having differentD values, but equalE value (|E|=0.00379 cm?1). The two triplets are assigned to two of the three carotenoids present in LHC II: lutein (|D|=0.03853 cm?1) and neoxanthin (|D|=0.04003 cm?1). The ADMR-detected Triplet-minus-Singlet (T—S) optical difference spectrum of the carotenoid (Car) triplet transition of LHC II showed, apart from bands in the Car absorption region, a contribution in the chlorophyll (Chl) absorption region due to a change in interaction between lutein and Chla at 670 nm, and neoxanthin and Chla at 670 and 677 nm. From Linear Dichroic (LD-)ADMR-detected LD-(T—S) spectra we have determined that the tripletz-axis (which corresponds roughly to the polyenal axis) of lutein and neoxanthin makes an angle of 47° and 38° with theQ y transition moment of their adjacent Chla molecules, for the Chls absorbing at 670 and 677 nm, respectively. TheT z triplet magnetic transition moment of lutein is parallel to the lutein singlet and triplet absorptions, whereas theT x axis of neoxanthin makes an angle of about 20 degrees with the optical transition moments of the carotenoid molecule. The major Chla absorption bands of the optical absorption spectrum and the ADMR-detected T—S spectrum is best explained by assuming that all Chla is present in dimers. It is proposed that a free Chl dimer absorbs at 664 and 670 nm, whereas a Chl dimer bound to a carotenoid absorbs at 670 and 677 nm. 相似文献
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Combination of Pd, supported on alkaline earth type supports with a lipase results in a selective catalytic system for dynamic kinetic resolution of benzylic amines. 相似文献